You can call the comprehensive housing management office and check the housing code.
2.
When someone comes to check the information of people living in the house every quarter, you can ask them your house code.
3.
You can consult the landlord about the house code.
4.
There will be a new house number at the door of each house, but it is not specific to the room number. If you want to apply for a temporary residence permit, you can say something nice and ask them to fill it out for you.